Cellular foamed alkyd-diisocyanate resins



Patented July 8, 1952 i: 1

. 2,602,783 IL'C ELLULAR FOAMED ALKYD-DIISOCYANATE RESINS' .1. Eli Simon, Los Angeles, and Frank W. Thomas,

v V Burbank, Calif., assignors to Lockheed Aircraft Corporation, Burbank, Calif.

No Drawing. Application January 14,1949,

Serial No. 71,087

11 Claims.

. This invention relates to the manufacture of formed cellular plastic materials andfrelates more particularly to the manufacture of improved cellular foamed alkyd resin-diisocyanate plastics incorporating or employing diisocyanate s no s ad t a en s, In our co-pending applications Serial No. 35,294 filed June 25, 1948, now Patent 2,577,279; Serial No.-44,993, filed August 18, 1948, now abandoned; Serial No. -50,007,- filed September 18, 1948, now Patent 2,577,280; and Serial No. 54,822, filed October 15, 1948, now 'Patent 2,577,281, we have disclosed methods and formulations for making lowdensity cellular foamed plastics in which the component ingredients maybe simply mixed together and poured into acavity or the-"like to react at atmospheric pressure so as to assume a foamed-cellularstate and so as to directly and immediately bond with the-walls of the cavity. The low'density of these materials coupled. with their other desirable physical characteristics and the easy anne ti whi thsyma be p d and u ed. adapts them for numerous applications in the fi ld of n.- ec ricale u nt. c- As described in our earlier applications for Letters Patent above referred to, the foamed cellular materials were obtained by reacting an alkyd resin and a oly-isocyanate mixture at atmospheric pressure, obtaining an eifective foam producing action by controlling the water content and/or by the mode in which the water is incorporated in the reactant mixture and/or by the employment of additives such asmetallic leafing :powders or metallic "'soap powders.

We have discovered that improvedicellular foamed alkyd-diisocyanate plastics may be prepared-by. employing high molecular Weight polyisocy'anate reaction products in the formulations for. the cellular foamed materials instead of the unmodified. diisocyanate or together with the unmodified diiso'cyanate; 'By appropriately utilizing these high molecular weight polyisocyanate reaction products in the primary formulations we obtain a more stable foaming reaction withless tendency for thecells to collapse. even in pourings-ormasses of large cross section, reduce the mixingtime required and therefore. lessen. the tendency forpremature reaction, and obtain a foamed cellular plastic material of 1 5 improved physical characteristics. When ,a high-molecular weight poly-isocyanate reactionproduct is used in .the formulation, the isocyanate-is more compatible with the alkyd resin 'so' that less mixing time is reguiredand,

therefore, there is less tendency toward premature reaction. It is, therefore, an object of the present invention to provide formulations for producing improvedjfoamed cellular plastic ma- 5terials. U

The employment of the high molecular weight resinous poly-isocyanate reaction products as the sole source of isocyanate groups for coupling with an alkyd resin in the preparation of the cellular foamed plastic, or the dilution or blending of such a resinous poly-isocyanate reaction product with a, substantially pure diisocyanate, for use in the 'allgyd resin-diisocyanate reactant mixture, has been found to produce foamed plastic having very small uniform cells thereby improving the physical properties'of the product. The cells may be inch or less in diameter, 'being' much smaller" than the cells obtained when the resinous, high molecular weight, poly isocyanate addition agent is not used. The smaller cell sizeimparts higher compressive strength to" the foamed 'material, improves the thermal insulating properties, and improves the shock resistance, flexibility and vibration resistance. j Furthermore, in the product having the small uniform cells there is ess t ally n notch f ct Whe ea w th h fo m plastics having the large cells the rupture of the boundary cell adversely affects not only an appreciable portion of the material due to a decrease in the load carrying area but, due to the large size of the ruptured cell, also produces a notch effect which materially lowers the strength characteristics of the material. It is, therefore, another object of the invention to provide a foamed cellular plastic material characterized by uniform cells of small diameter and possessing improved physical characteristics.

' The. foregoing advantages are v-obtained j with no increase in. weigh,t,..tha t is, without rincreas:

ing the density of the foamed cellular plastic products.

The invention provides high molecular weight poly-isocyanate resinous'additioniagents for use in the production "of cellular :foa'rned' alliyd -di isocyanate plastics and" more specifically is concerned with the "resinous reaction "products of meta-toluene diisocyanate ;apd icp nipqurids having m than lular plasticfmaterials, H I

drogen mac w li he meta vention comprehends generally the preparation or mixing of an alkyd resin and a meta-toluene diisocyanate resinous addition agent, of the type just referred to. employed either individually with the alkyd resin or in conjunction with pure meta-toluene diisocyanate and the alkyd resin. Further, the invention comprehends, when de-- sired, the incorporation in the reactant mixture of a metallic soap powder or a metallic leafing powder Or in place of the metallicsoap I powder or leafing powder, the reactant mixture may further include addition agents which act as fire retardants. In each case the reactant mixture is poured or applied after suitable mixing and is allowed to react at atmospheric pres-.

From 3 hydroxyl (OH) 1 carboxyl (COOH) To 4 hydroxyl (OH) carboxyl (COOH).

It has been found desirable to employ resins having an acid number between approximately and approximately and wherein the ratio of the hydroxyl groups to the carboxyl groups is 2 to 1 although satisfactory results have been obtained by employing resins having the foregoing ranges of acid numbers and ratios of the hydroxyl to carboxyl groups in their reactants. The following formulae have been found to be suitable for preparing unmodified alkyd resins from polyhydric alcohols and polybasic acids. Formula A yields a resin having an acid number of from 5 to 80, preferably approximately 15, and a water content of about 0.3% by weight.

Excellent results have been obtained by employing the resin of Formula A having an acid number of 16 and a water content of 0.56% by weight and by employing the resin of Formula C having an acid number of'20 and a water content of 0.85% by weight. The ratios of the hydroxyl groups to the carboxyl groups of the alkyd resin reactants in Formulae A, B, C and D are respec- 76 1(OH) :1(COOH).

4 tively 2(OH) :1(COOH), 2(OH) :1(COOH). 2(OH) 1(COOH), and 1(OH) 1(COOH). In Formula A the range of proportions may be from 3 to 5 mols of glycerol, from 1.5 to 3 mols adipic acid, from 0.1 to 1.5 mols phthalic anhydride and in Formula C the practical operative range of proportions is from 3 to 5 mols trimethyiol propane, from 1.5 to 8 mols adipic acid and from 0.1 to 1.5 mols phthalic anhydride.

The following Formulae E, F and G are typical or representative of formulae for preparing unmodified alkyd resins from single polyhydric alcohols and single polybasic acids producing resins suitable for use in the method and products of the invention:

Formula E Mols Glycerol 4 Adipic acid 3 Formula F Mols Trimethylol propane 1 3 Phthalic anhydride 2 Formula G Mols Glycerol 1 Phthalic anhydride 1.5

Th respective ratios of the hydroxyl groups to the carboxyl groups of the alkyd resin reactants of Formulae E, F and G are 2(OH) 1(COOH). 9(OH) 24(COOH) and 1(OH) 1(COOH).

Formulae H and I are examples of alkyd resins, oil modified, that have been found to be practical and operative in preparing the foamed cellular plastic materials in accordance with the present invention. The respective ratios of the hydroxyl groups to the carboxyl groups in the alkyd resin reactants of these formulae are 3(OH) 3 /2(COOH) and 6(OH) 7(COOH).

Another example of an oil modified alkyd resin which we have found to be practical and effective in preparing the foamed cellular plastic material is found in Formula J where the ratio of the hydroxyl and carboxyl groups of the alkyd resin reactants is .10 /2(0H). 9(COOH) and where the (OH) group inthe ricinoleic .acid, or the 3(OH) groups for the castor oil molecule, is taken into account or 7%(OH) 9(CO0H) when the (OH) groups in the ricinoleic acid is not considered.

Formula J Mols Glycerol 2.5 Adipic r. .4 Castor oil I. .1 Maleic anhydride r.- -l An example of a natural resin modified alkyd resin suitable for incorporation in, the cellular foamed plastics of the invention is set forth in Formula K- where the'ratio of the hydroxyl to the carboxyl groups of the alkyd resin reactants is Glycerol gram mol' Sebacic acid gram mols 1 A; Resin copal grams 100 I Formula L Phenol 50 grams Formaldehyde 17 grams Rosin 65 grams Phthalic anhydride 30 grams or 0.2 gram mol Glycerol 18.4 grams or 0.2 gram mol We have found that the most satisfactory results are obtained'when the water content range of the alkyd resin "component or components of the diisocyanate alkyd resinreactant mixture is irom 0.1% to 3.0% by weight. without regardto the specifiemanner of incorporating the'water inthe mixture. "Inthe'typicalformulae and:exampl'es herein set forth itwill be considered that the water component (H2O)" of the diisocyanate alkyd resin reactantmixture is incorporatedby dissolving a calculated amount of the water in the selected alkyd resin and suitably agitating the resin-water mixture so that the alkyd resin component will contain the'selected proportion of water. However; as set forth in our co-pending application, Serial 'No. 35,294, now 'Patent No. 2,577,279 the water maybe incorporated in the reactant mixture in combination with anon-ionic wetting agent or by the use-of one or more metallic salt hydrates. v The is'ocyanate employed in preparingthe above mentioned resinous addition agents for use in the reactant foam'producing mixture is preferably meta-toluene diisocyanate. The addition .agents are the reaction products of meta-toluene diisocyanate and compounds having more than one functional group or. radical, each, o said groups or radicalscontainingat least one labile hydrogen-atom that will react with the meta-toluene diiso'cyan'ate by'addition polymerization. 5 .Inother words, the addition agentsare the reaction prodnets of addition polymerization 'betweenjmtatoluene idiisocyanate' and polyfunctional" mole cules, each functional group containing atleast one labile hydrogen atom. "The reaction is preferablyl carried outfin an excess of} the metatoluene'diiso'cyanate to producea resinous viscous product readily compatible. with the alkyd resins of the reactant mixture. The degree of reaction is controlled by amineequivalent determinations, the amine equivalentabeing' defined. in this app catiQn-asthenum er o arms o an isocyanate consumed by. Q 1 1 am 3 9.1 9 e o dar am intheforma'tion oi the corresponding-urea flghus the theoretical Jamin'e 'equivalent of chemically e diisocyanate s '87,;as shown sin-east ne X Y i \(a secondaryamine):

" (lzleta tolue .diisecyana 'i:. j i .lmolebular weight- 174) Weight=%1=87? i j (A substituted urea) W-h'en the resinous, high molecular weight diisocyanate is to'be used as an addition agent to -substantiallychemic'ally' pure meta-toluene dii'soc'yanate, -'it is=preferred to prepare it by reactingftwo mols-of chemically-pure meta-toluene diisocyanate' with" one mol of a polyfunctional compound toa polymerization degree such that when diluted with the un-reacted meta-toluene diisocyanate, the resulting solution has an amine equivalent of between 1-00- and-175 with an amine equivalent of between and being preferred, as will be later described. Thefunctionality of the compound to be reacted with the meta-toluene diisocyanate is considered as being governed by the number of groups per molecule that contain at least one labile hydrogen atom per group. The following compounds, included in groups 1 to 8 inclusive, which fall within the definition just given, are. suitable for polymeri zatio'n' with the meta-toluene diisocyanate in the preparation of the addition agents:

1. Polyfunctional aliphatic alcohols-diols having a functionality of 2:

2 methyl, 294 pentanediol 1,4-hexanediol 1,5--pentanediol 1,7-heptanediol 1,4-heptanediol Ethylene glycol Diethylene glycol (l) Resorcinol (m-dihydroxybnzene) (2) Pyrocatechol (o-dihydroxyzenzene) (3) Pyrogallol (trlhydroxybenzenef 3. Bi-funotional metallic soaps (having a functionality of 2) v k These compounds may be representedby'the io ams /OH RO-M where R a fatty acid rs iduesucha's stearate, palmitate, oleate and'laurate, and M a metal having a valency greater than 2, such as aluminumtt e and ismut I Exampl s i sus n n i i lalfih lii s e 1. 4. Polyfunctional aliphatic amino alcohols (having a functionality of 2 and 3) (1) Z-amino, l-butanol (2) 2-amino, Z-methyl, 1-3 propanedlol (3) 1,3-amino, Z-propanol (4) Amino ethyl alcohol (5) 4-amino, Z-butanol (6) 2-amino, 2-methyl, l-propanol (7) Z-amin'o, 2-methyl, 3-hexanol It is to be understood that although amines, such as a primary amine, may theoretically contain more'thanone labile-hydrogen'atom, we do not herein, in determining the functionality, consider each replaceable hydrogen atom of the same group as being'equivalentto a function of 1. On the other hand, -as previously indicated, in the ,present description of the invention, we consider functionality in terms of groups rather than in terms of the total'number of labile hydrogen atoms butin order for a group to be considered as functional it'mustcontain at least one labile hydrogen atom. Thus in the case of 2-amino, l-butanol We speak of this compound as having a functionality of 2," there being two groups present, each group having at least one labile hydrogen atom. In a like manner, hexamethylene diamine is considered as having a functionality of two rather than a functionality of four.

5. Polyfunctional aminophe'nols (having a functionality of 2) I (1) o-Aminophenol (2) m-Aminophenol (3) p-Aminophenol 6. Polyfunctional aliphatic amines (having a functionality of 2):; v j i (1) Hexameth-ylerie di-amine (2) Trimethyle'ne diainine (3) 7 1,3 diaminobu'tane (4) Tetramethylene diamine 7. Polyfunctional aromatic amines (having a functionality of 2) (1) m-Toluene diamine. (2) o-Phenylenediamlne (3) m-Phenylene diamine (4) p-Phenylene diamine' 8. Polyfunctional thio glycols (having a functionality of 2): (l) Mono-thio glycols-(a) monothio-ethylene glycol 1 v CHIOH er-hen (2) Di-thio glycols-(a) dithio-ethyleneglycol 3'31 3 3;; 7

state;

merization between" meta-toluene diisocyanate and 2-methyl, 2,d-pentanediol:

H H CH:

The reactive high molecular weight polyisocyanate is thought to be more compatible or more readily incorporated with the alkyd resins in the foam producing reaction because of the intervening somewhat polar aliphatic structure. Furthermore, when the high molecular weight reactive polyisocyanate is coupled with an alkyd resin, a higher molecular weight reaction product is immediately formed than would be the case when chemically pure meta-toluene dlisocyanate is employed. It is believed that the formation of this higher molecular weight reaction product materially contributes to the more uniform foamingand especially to the production of small cells since it favors the entrapment of gas in the more viscous medium with the subsequent controlled expansion of the Plastic mass so that the rate of blow more closely approximates the rate of cure of the foamed cellular plastic material. It is also believed that the resultant higher molecular weight reaction product between the resinous polyisocyanate and the alkyd resin has increased elasticity without loss in plasticity so that the cells that are formed are strengthened.

The reaction products of the mea-toluene diisocyanate and'the polyfunctional molecules may replacejentirely the unmodified meta-toluene diisccyanate in the alkyd-resin meta-toluene diisocyanate reactant mixtures or formulations of the characterset forth in our eo-pending applications aboveiidentified, or may be used in conjunction with orblended with the unmodified meta-toluene diisocyanate in the reactant mixtures. In either instance it is preferred that the resultant or total polyisocyanate reagent has an amine equivalent. between. and with the preferred range of'the amine equivalency being between 100 and 150. 'I'he following is illustrative of the preparation of a modifleddiisocyanate of the invention "adapted to be used as the sole source of diisocyanate in the alkyd-resin-diisocyanate reactant mixture for making the cellular foamed plastic material: In the reaction between 1.75 grams of 2-methyl, 2-4 pentanediol and 19,125 grams of chemically pure meta-toluene diisocyanate with the reactant ratio as indicated in the foregoing, that is, between 2 mols oi the meta-toluene diisocyanate to 1 mol of the diol," it will require 5.17 grams of the meta-toluene diisocyanate to react with the 1.75 grams of the diol. This will produce 6,92 grams of a high molecular weightdiisocyanate havin: a molecular 9; weight of 466 or by the above definition an amine equivalent or 233. Thisreaction is as follows:

(Molecular weight, 174) Thus: it will require (2x174) or 348 grams of meta-toluene diisocyanatefto' react with 118 grams of Z-methyl, 2-4 pentanediol or to react with the 1.75 grams of the diol.

The unreacted. meta toluene diisocyanate is 13.96 grams, i. e. (19.125-517) The percentage by weight of the high molecular weight. polyisocyanate reaction product is 33 that. is,

The theoretical amine-equivalent is the amineequivalentof the'chemically pure metatoluene diisodyanate 'b'eingB'lj and that of the resinous reaction product being meta-toluene diisocyanate and"2-methyl, 2-4 pentanediol being 233. In anactual periormance 'of" this reaction the determined amineequival'ent of the prepara'-' tion was 145.:v The anaylsiswas conducted by adding an excess of a 2 N solution of di-n-butylamine to a known weight jofthe resinous polyisocyanate andback; titrating the excess di-nbutylamine, using bronipheriol blue indicator, with a lNsolution ofhydr'ocl'iloriciacid'.

Where the reaction productoithe meta-toluene diisocyanate and ,the polyi'unctionalmolecules is to be .diluted or blendedwith' unmodified metatoluene diisocyanate to constitutethe pulyisocyanate reagent or ingredient of the polyisocyanate-alkyd resin reactant mixture, the reaction between the meta-toluene diisocyanate and the polyfunctional molecule compound is taken more nearly to completion to obtain a higher molecular weight polyisocyanate, that is a polyisocyanate having a higher amine equivalent. This reaction product isthen diluted or blended with meta-toluene diisocyanate, preferably in a chemically pure state, to obtain a reagent having an amine equivalent of from 100 to 175, preferably an amine equivalent of between 100 and 150. An example of this type of reagent may be prepared from meta-toluene diisocyanate and 2-methyl, 2-4 pentanediol or other of the above named polyfunctional molecule compounds, Gonsider the polymerization'between 2-methyl, 2-4: pentanediol and meta-toluene diisocyanate carried to an average polymer molecular weight of approximately 5,000, having terminal isocyanate groups, and represented by following illustrative reactions:

(Molecular weight, 118) =5g17 grams 2-metl1yl 24 pentanediol T Meta-toluene 'diisocyanag methyl, 2-4.- pentanediol." v

N=o=o I J (Molecular weight=518) I where HO--ROI-Irepresents a. molecule of 2- Since this high molecular weight isocyanate has a molecular weight of 5138 and two isocyanate groups per. molecule, then by previous definition, it has an amineequivalent of I A very small percentage of such a high molecular weight reactivepolyisocyanate suffices to provide the necessary modification of the amine equivalent. This technique also furnishes .a con venient means-of regulating the amine equivalent. Thus, at 1% by weightaddition to metatoluene diisocyanate, the resulting reagent has an amine equivalent of and on a 2% by weight addition basis the resultant reagent has an amine equivalent of 136.6.

The following examples of the' modified poly isocyanate reagents contain suflicient proportions of the meta-toluenediisocyanate to be employed in the cellular foamed plastic reactant mixtures. The final polyisocyanate reagent comprises aso lution of high molecular weight polyisocyanate reaction products in excess metal-toluene diisocyanate and may be prepared either .as an integraL-solution, i. e., without further blending with unmodified meta-toluene diisocyanate, or prepared separatelyand thenblended with op meta-toluene .diisocyanate; in each case the final blend having an'amine equivalent of between '100 and '1-7 5, and preferably between -1 00 and-15.0,

and being within thereactantgrange gqf propor- Y WMZQ Y i Mols 2 methyl, 2-4 pentanediolnn'n 410.065 Metatoluene jdiisocyanate 1' In Example :I the permissible range of proportions is from 0.01 to 025 mol'of the 2 methyl,2.--4 pentanediol per mol of- ;the meta-toluene diisocyanate.

o-Dihydroxybenzene 11 Erample VI i Mols Toluene diamine :065 Meta-toluene diisocyanate 1 Eaiample VII Mols m-Dihydroxybenzene A 0.065 Meta-toluene diisocyanate 1 In Examples II to VlI inclusive, preferred proportions are set forth,however, the permissable ranges of proportions are the same as in 1 Zinc stearate Aluminum stearate Barium stearate Zinc laurate Calcium stearate Calcium oleate Magnesium stearate Strontium stearate Magnesiumhydroxy stearate The proportion of the metallic soap powder employed may be varied considerably. Thus, it has been found that from gram to 7 grams of the selected metallic soap powder may be used for each 30 grams of the alkyd resin in the diisocyanate-alkyd resin reactant mixture.

As set forth in our co-pending application, Serial No. 44,993, filed August 18, 1948 and now abandoned, we have discovered that the incorporation of metallic leafing powders in the alkyd resin-polyisocyanate mixture, results in a foamed cellular plastic product of superior physical properties. The leaflng powders must have the property of leafing when suspended in a suitable liquid vehicle and when so suspended and applied as a paint have the ability of forming a continuous film on the surface of the applied vehicle or paint. Such powders are produced by treating small pieces of metal in a stamping mill with subsequent screening and polishing. It has been found that some aging is required to obtain the best leaflng action of the powders. The metallic leaflng powders which we have found to be practical and effective in the formulations of the invention include:

Aluminum leaflng powder Aluminum bronze leaflng powder Gold bronze leanng powder Copper bronze leaflng powder Lead leafing powder Nickel leafing powder Stainless steel leaflng powder (18 8 chromiumnickel) Silver leaflng powder Gold leafing powder Copper leai'lng powder Excellent results have been obtained by employing aluminum leafing powder of such fineness that not more than 2% is retained on a Number 325 sieve and by employing aluminum bronze leafing powder, gold bronze leafing powder and copper bronze leaflng powder of such fine ness that not more that 0.3%; is. 'retainedonia Number sie've. Themetallicdeafing'powders employed individually or in appropriate mixtures may be used in the proportion of from 1 6 to 7 grams for each 30 grams of the alkyd resin in the polyisocyanate-alkyd resin reactant mixture. f

Excellent results have been obtained when both a metallic soap powder and a metallic leafing powder are incorporated in the polyisocyanatealkyd resin mixture. The combination of the fillers appears to act :synergistically, that is the combination of the metallic soap powderand the metallic leafing powder causes the formation of a greater volume of the cellular plastic than if the same proportionate quantity of each individual filler is used separately in the identical polyisocyanate-alkyd resin reactant mixture. When both the metallic leafingpowders and the metallic soap powders. are usedin the formula: tions of the invention, the metallic leafing powder may be employed in the proportion ofi'rom to 5 grams for each 30 grams of the alkyd resin and the metallic soap may be used in the proportion of from to 5 grams for each gram of the alkyd resin.

The foamed cellular plastic products of the invention may bemade flame resistant and selfextinguishing when once ignited by incorporating flame retardantadditives in the polyisocyanatealkyd resin reactant- -mixtura- The additives which we have found to be eflectivein rendering the cellular material flame resistant are unsaturated alkyl esters of aryl phosphonic acids, namely compounds having the general formula--- I ArPO,(O CHzCR CHR )2 where Ar-represents and and alkaryl hydrocarbon radicals and R and R are hydrogen and. alkyl hydrocarbon radicals. Compounds; of this .character are describedin United States Letters Patent No. 2,425,765 issued August 19, 1947. Included in this group of compounds are:

1. Diallyl phenyl phosphonate i 2. Bis (methallyl) benzenephosphonate CHF=0CH:OIQOCH;-C=CH:

Ha I CHI and, a v

3. Diallyl toluene phosphonate O oH,=o-orr,-o-i -o-cm-o=cr1, II I I H These additives not only serve to impart flame resistance and decrease flame propagation characteristics to the foamed cellular plastic product but also unexpectedly, serve to materially decreasethedensity of the foamed material. The proportion of the selected fire retardant and flame-proofing additive employed in the poly isocyanate-alkyd' resin reactant mixture may be varied considerably but in practice from 1 gram to 20 grams of the additive may be used with each 30 grams of the alkyd resin. It is usually preferred to employ approximately 5 grams of the additive for each 30 grams of the alkyd resin.

If desired, other flame-proofing and fireretardant agents maybe employed "together with or in addition to the'unsatur'atedalkyl estersof aryl phosphonic acids describedabovei Such fire retardant and flame-proofing agents-include tri-. chloralkyl phosphate of the general formula:

claim-9 011501 I J' 19. where R1, R2 andRs are alkyl-groups having from 2 to 4 carbon atoms, antimony' oxide SbzOs and unsaturated alkyl esters of the alkenyl phosphonic acids of the class described in United States Letters Patent No. 2,425,766, issued August 19, 1947, namely compounds having the general formula: R REC CR4PO QCH2CR CHR 2 where R, R and R are hydrogen or alkyl, and R and R are hydrogen, alkyl or aryl radicals.

Examples of the tri-chloralkyl phosphates which we have found to be effective inthe formulations of the invention are:

Tri-B-chlorethyl phosphate and V Trichlorpropyl phosphate Examples of the unsaturated alkyl esters of alkenyl phosphonic acids which we have found to be practical and effective in the cellular plastic formulations are: v

Diallyl isobutene phcsphonate Bis (methallyl) styrene phosphonate CH! 0 .CH:

cmr-e-orc-oi o dln th m; E

lLo=g I n o and in addition to serving as'aflame-proofing agent, acts as a cell size regulator whereby the cells of the foamed plastic are of smaller'size. The unsaturated alkyl esters of alkenyl phosphonic acids may be usedin the proportion of from 1 to 20 grams for each 30 grams :of the alkyd resin when employed without the unsaturated alkyl esters of aryl phosphonic-acids previouslyinamed. The tri chloralkyl phosphates maybe used in the proportion of .fr'omf /2 to'lO gramsiior each 3 grams of the alkyd resinfa'nd when "'used' with unsaturated alkyl esters of aryl phosphonic acids in the proportion above'set forth, may be used in the proportioncf Mata? gram for each ,30 grams of alkyd resins El e-antimony oxide may be employed inthe proportion of from A; to 5 grams for each 30 grams of the alkyd resin with or without the, addition of the unsaturated alkyl esters of aryl phosphonic acid or the tri chloralkyl phosphates.

Therfollowing are typical illustrative: examples of i the polyisocyanatia-alkyl formulations; of the invention productive {of 51 low" density cellular foamed plastic materials-characterized by small uniform cells and superior physical properties:

- ram-n71;

' V v V Grams kyd resin of Formula A having an acid number of 16 a ater content of 0.5 by

weight 3O Polyisocyanate reagent o'f'Example I 20 Zinc; stearate in Example 1, noun-l0 grainsLof-the poly 1socyanatereagent and fromqkto 7 /2 grams of the zinc stearate mayib'e' used with each 30 grams ofthealkydresin. 1

Endbicl'le 2 Grams Alkyd resin of Formula C having an acid number of 20 and awater content of 0.85%, by

weight -'L--- '30 Polyisocyanatereagent of Example I. 20 Aluminum stearate powders; 1

In this formulation, 10 to 40 grams of the polyisocyanate reagent and from .1 to 7 grams of the aluminum stearate powdermay be used with each 30 grams of the alkyd resin. 1

Emma c Grams Alkyd resinof Formula Ahavingan acid number of 16 and a; water content of 0.56 by Weight 30 Polyisocyanate reagent of Example II 20 Magnesium hydroxy stearate powder 1 Polyisocyanate reagent of Example IlI 20 Calcium stearate powder r 1 In Example 4, from .10 .toAOgrams of the polyisocyanate reagent and froma a .to 7 grams of the calcium stearate powder may-be used for each 30 grams ofthe alkyd resin; J' Y "Ezamkf. Grams Alkyd resin of Formula A having an acid number of 16 and a water content of 0.56% by weight 30 Polyisocyanate reagent of Example IV 20 Zinc stearate powder; =54; Calcium stearate.powder A;

It will be observed that in Example 5, the formulation incorporates a mixture or combination of metallic soappowders. v

Example 6 v f I Grams Alkyd resin of Formula C having an acid number of 20 and a water content of 0.85% by weight 30 Polyisocyanate reagent of Example Vl 20 Aluminum lea'fing powder of No. 422 Mesh,

by weight 30 Polyisocyanate reagent of Example VII' 20 Copper lining powder 1 Example 9 Grams Alkyd resin of Formula H having an acid number of 40 and a water content of 0.60%

by weight 30 Polyisocyanate reagent of Example VI 20 Stainless steel lining powder 1 Example 10 Grams Alkyd resin of Formula A having'an acid number of 16 and a'water contentof 0.56%

by weight 30 Polyisocyanate reagent of Example I 20 422 Mesh aluminum leafing powder 1 Zinc stearate powder A;

In Example 10, from 10 to 40 grams of thepolyisocyanate reagent,'from to 5 grams. of the aluminum leafing powder, and from 1 5' to5grams of the zinc stearate powder may be used for each 30 grams-of the alkyd resin.

Example 11 Grams Alkyd resin of Formula'C'having an acid number of 20 and a water content of 0.85% by weight 30 Polyisocyanate reagent of Example V 20 Strontium stearate powder 0.75 422 Mesh aluminum leaflng powder 0.75

Example 12 Grams Alkyd resin of Formula A. having an acid number of 16' and a water content of 0.56%

by weight 30 Polyisocyanate reagent of Example I 20 Zinc stearate powder -n Diallyl phenyl phosphonate 5 16 In Example 12 from 10 to 40 grams oi -the polyisocyanate reagent. from to 7 /2j'grams'of the zinc stearate powder, and from 1 to 20 grams of the diallyl phenyl phosphonate may be used with each 30 grams of the alkyd resin.

Example 13 1 Grams Alkyd resin of Formula A having an acid number of 12 and a water content or 0.75% 1 1 by weight -J; 30 Polyisocyanate reagent of Example II 20 Aluminum stearate powder; 1 Tri-B-chlorethyl phosphate 2 /2 In the formulation of Example 13, from 10 to 40 grams of the polyisocyanate reagent, from 1 6 to 7 /2 grams of the aluminum stearate powder and from to lll grams of the tri-B-chlorethyl phosphate may be used for each 30 grams of the alkyd resin,

, Example 14 g I Grams Alkyd resin of Formula L having an acid number of 50 and a water content of 1.25%

by weight 30 Polyisocyanate reagent of Example III 23 Zinc stearate powder I 1 Antimony oxide powders"; 2

Example 15 Grams Alkyd resin of Formula A having an acid number of 16 and a water content of 0.56%

by weight 30 Polyisocyanate reagent of Example I 20 Zinc stearate powder 1 Diallyl phenyl phosphonate 5 Benzoyl peroxide -1 A In Example 15, from 10 to 40 grams of the polyisocyanate reagent, from 1 to 7 /2 grams of the zinc stearate and from 1 to 20 grams of the diallyl phenyl phosphonate may be employed with each 30 grams of the alkyd resin. The benzoyl peroxide employed in this and other formulations of the invention for obtaining fire retardant foamed cellular materials is preferably predissolved in the fire retardant additive and its proportion is preferably approximately 5% by weight of the unsaturated alkyl esters of the aryl phosphonic acids or of 'the alkenyl phosphonic acids.

Example 16 Grams Alkyd resin of Formula E having an acid number of 30 and a water content of 1.5% by weight 30 Polyisocyanate reagent of Example VI 22 No. 422 Mesh aluminum leafing powder 1 Diallyl phenyl phosphonate 3 Benzoyl peroxide 0.15

Example 17 Grams Alkyd resin of Formula A having an acid number 01 16 and a water content of 0.56% by weight 30 Polyisocyanate reagent of Example I, having an amine equivalent of 20 No. 422 Mesh aluminum leafing powder--- 2 Zinc stearate powder Diallyl phenyl phosphonate 5 Benzoyl peroxide;

0.75% by weight--. 30 Polyisocyanate reagent of Example IV,

having an amine equivalent of 110 20 No. 422 Mesh aluminum leafing powder 0.75 Diallyl phenyl phosphonate 5 Zinc stearate powder 0.75 Benzoyl peroxide Example 19 Grams Alkyd resin of Formula having an acid number of 20 and a water content of 0.85% by weight 30 Polyisocyanate reagent of Example I, having, an amineequivalent of 105 20 Zinc stearate powder 1 I Diallyl phenyl phosphonate 5 Benzoyl peroxide Example 20 I Grams Alkyd resin of Formula A having an acid number of 16 and a water content of 1.1% by Weight 30 Polyisocyanate reagent of Example VI having an amine equivalent of 155 20 Zinc stearate powder 2 Diallyl phenyl phosphonate 5 Benzoyl peroxide Example'Zl Grams Alkyd resin of Formula C'having an acid number of 20 and a water content of 0.85% by weight"; 30 Polyisocyanate reagent of Example V having an amine equivalent of 155 20 Zinc stearate powder 1.0 Diallyl phenyl phosphonate 5 Benzoyl peroxide Example 22 Grams Alkyd resin of Formula C having an acid number of 20 anda water content ,of 0.85% by weight 30 Polyisocyanate reagent of Example I having an amine equivalent of 105; 20 No. 422 Mesh aluminum leafing powder Zinc stearate powder 1 /2 Diallyl phenyl phosphonate 5 Benzoyl peroxide Example 23 V Grams Alkyd resin of Formula C having an acid number of 20 and a water content of 0.85% by weight 30 Polyisocyanate reagent of Example I hav- I ing an amine equivalent of 120 20 Zinc stearate powder 1 Diallyl phenyl phosphonate 5 Benzoyl peroxide Example 24 Grams Alkyd resin of Formula 0 having an acid number of 20 and a ,watercontent vof 0.35% by weight 30 Polyisocyanate reagent of Example I having an amine equivalent'of'145 20 Zinc stearate powder 1 Diallyl phenyl phosphonate. a 5 'Benzoyl peroxide A Example 25 v Grams Alkyd resin of FormulaC having an acid) number of 20 anda' watercontent of 0.85% by weight 30 Polyisocyanate reagent of Example VII having an amine equivalent of 20 Zinc stearate powder; 1 Diallyl phenyl phosphonate 5 Benzoyl peroxide A,,

In the formulations of Examples 16 to 25, the

ranges of proportions of the polyisocyanate reagent, metallic leafing powders, metallic soap powders and the flame-proofing and fire retardant agents may be substantially'thesame as in the foregoing examples.

In carrying out the method of the invention in the preparation of the foamed cellular plastic materials, the selected high molecular'weight polyisocyanate reagent and the selected alkyd resin are first obtained or produced in accordance with the above disclosure. The reagent and the other ingredients of the desired formulation are then simply mixed thoroughly in the ratio designed to produce the foamed plastic having the desired density, etc. This mixture is then poured into the mold or cavity in the structure in which it is to form a part or is applied to a structural surface, or the like, and is allowed to react at atmospheric pressure either with or without the application of external heat or attended-by a moderate heating of, say, between F. and 150 F. depending upon the size of the batch. The mixture is merely allowed to react and the reaction ispermitted to go on to completion to produce the foamed cellular product. A post-curing operation of from 10 to 20 hours at a temperature of from F. to 225 F. may be desirable to continue the polymerization of the reaction and thusjobtain a stronger, more heat stable and more solvent'resistan't material. The foamed cellular plastic material obtained by the method has a substantially uniform cellular structure throughout characterized by small non-communicating cells of, uniform size and configuration. 9

It should be understood that the invention is not based upon or dependent .upon the theories which we have expressed. Nor is the invention to be regarded as limited to the express procedure or material set forth,.these details being given only by way of illustration and to aid in clarifying the invention. We do not regard such specific details as essential to the invention except insofar as they are expressed by way of limitation in the following claims infwhich it is our intention to claim all novely inherent in the invention as broadly as is permissible in View of the prior art.

We claim:

l. A foamed cellular plastic material which comprises the reaction product of an alkyd resin having 'an acid number of from 5 to 80 and a water content offrom 0.1% to 3% by weight and wherein the hydroxyl and carboxyl groups in the alkyd resin reactants are in the ratio of from 3(OH) :'1(CfOOI-I) to 4(OH) :5(COO II); a meta-toluene diisocyanate solution-containing as foam stabilizing agents high molecular-weight polyisocyanate reaction products obtained by the reaction ofmaterials consisting of one'mol of meta-toluene diisocyanate and .f rom1 approximately 0.01 to approximately 0.2 5jmol'of a compound having two] functional groups each of which contains a hydrogen atom that reacts with meta-toluene diisocyanate by addition polymerization, and the diisocyanate-polyisocyanate solution having an amine equivalent of between 100 and 1'75and a metallic soap powder chosen from the group consisting of Zinc stearate Strontium stearate Aluminum stearate Magnesium hydroxystearate Calcium stearate. Zinc laurate Magnesium stearate Calcium oleate Barium stearate in proportion of from 35 to 150 parts by weight of said solution and from 0.21 to 25 parts by weight of said metallic soap powder for each 100 parts by weight of said alkyd resin.

2. A foamed cellular plastic material comprising the reaction productof an alkyd resin having a water content of from 0.1% to 3% by weight, an acid number of from 5 to 80 and wherein the hydroxyl and carboxyl groups of the alkyd resin reactants are in the ratio range of from 3(OI-I) :1(COOH) to 4(0H) 15(COOH, and from 35 to 150 parts by weight for each 100 parts by weight of said resin of a metatoluene diisocyanate solution containing as foam stabilizing agents high molecular weight polyisocyanate reaction products obtained by the reaction of materials consisting of one mol of meta-toluene diisocyanate and from approximately 0.01 to 0.25 mol of a compound having two functional groups each of which contains a hydrogenatom that reacts with meta-toluene diisocyanate by addition polymerization, and the diisocyanate-polyisocyanate solution having an amine equivalent of between 100'and175, and from 0.4 to 25 parts by weight to each 100 parts. by. weight of said alkyd resin of a metal leafing powder chosen from the roup consisting of:

Aluminum leafing powder Aluminum bronze leafln'g powder Gold bronze leafing powder Copper bronze leafing powder Lead leafing powder Nickel leafing powder Silver leaflng powder Gold leafing powder Copper leafing powder Stainless steel leafing powder.

3. A foamed cellular plastic material comprising the reaction product on an approximate weight basis of an alkyd resin having a water content offrom 0.1% to 3% by weight and an acid number of from 5 to 80 and wherein the hydroxyl and carboxyl groups in the alkyd resin reactants are in theratio range of from 3(OH) 1(COOH) Strontium stearate Magnesium hydroxystearate Zinc laurate Calcium oleate.

Zinc stearate Aluminum stearate Calcium stearate Magnesium stearate Barium stearate 4. The foamed cellular plastic material which comprises the reaction product of an alkyd resin having an acid number of from 5 to and a water content of from 0.1% to 3% .by weight prepared from glycerol, adipic acid and phthalic anhydride in the proportion of from 3 to 5 mols glycerol, from 1.5 to 3 mols adipic acidand from 0.1 to 1.5 mols phthalic anhydride; a metatoluene diisocyanate solution containing as foam stabilizing agents high molecular weight reaction products obtained by the reaction of materials consisting of one mol of meta-toluene diisocyanate and approximately 0.01 to approximately 0.25 mol of a compound having two functional groups each of which contains a hydrogen atom that reacts with meta-toluene diisocyanate by addition polymerization, and the diisocyanate-polyisocyanate solution having an amine equivalent of between and 175; and a metallic soap powder chosen from the group consisting of:

Strontium stearate Magnesium hydroxystearate Zinc stearate Aluminum stearate Calcium stearate Magnesium stearate Zinc laurate Barium stearate Calcium oleate in the approximate proportion of from 35 to 150 parts by weight of said polyisocyanate solution and from 0.21 to 25 parts by weight of said metallic soap powder for each 100 parts by weight of said alkyd resin.

5. A foamed cellular plastic material comprising the reaction product of an alkyd resin having an acid number of from 5 to 80 and a water content of from 0.1% to 3% by weight and wherein the hydroxyl and carboxyl groups in the alkyd resin reactants are in the ratio range of from 3(OH): 1(COOH) to 4(OH): 5(COOH); and a product obtained by the reaction of materials consisting of one 'mol of meta-toluene diisocyanate and from 0.01 to 0.25 mol 2 methyl, 2-4 pentanediol, said product having an amine equivalent of approximately and a metal leafing powder in the approximate proportion of from 35 to parts by weight of said product and from 0.4 to 25 parts byweight of said leafing powder for each 100 parts by weight of said alkyd resin.

6. A foamed cellular plastic material comprising the reaction product of an alkyd resin having an acid number of from :5 to 80 and a water content of from 0.1% to 3% by weight and wherein the hydroxyl and carboxyl groups in the alkyd resin reactants are in the ratio range of from 3(OH): 1(COOH) to 4(OH): 5(COOH) and a product obtained by the reaction of materials consisting of one mol of meta-toluene diisocyanate and from 0.01 to 0.25 mol O-dihydroxybenzene, said product having an amine equivalent of between 100 and 1'75 and a metallic soap powder chosen "from the group consisting of:

Zinc stearate Aluminum stearate Calcium stearate Magnesium stearate Zinc laurate Barium stearate Calcium oleate in the approximate proportion of from 35 to 100 parts by weight of said reagent and from 0.4 to 25 parts by weight of said metallic soap powder for each 100 parts-by weight of said alkyd resin.

7. A foamed cellular plastic material comprising the reaction product on an approximate Strontium stearate Magnesium hydroxystearate 21 a weight basis of an alkyd resin having a water contentof from 0.1% to 3% by weight prepared from glycerol, adipic acid and phthalic anhydride. in'ftlie proportion] ofnir'om 3 to'5 mols 'gly'cerohfrom' 115' to 3i'nolsfl'adipic acid and from 0.1 to 1.5 mols phthalic anhydride. from Zinc stearate Aluminum stearate Calcium stearate Magnesium stearate Barium stearate 8. A foamed cellular plastic material comprising the reaction product on an approximate weight basis of an alkyd resin having a water content of from 0.1% to 3 by weight prepared from 4 mols trimethylol propane, 2.5 mols adipic acid and 0.5 mol phthalic anhydride and having an acid number of from 5 to 80; from to 40 grams for each 30 grams of said alkyd resin of a product obtained by the reaction of materials consistin of one mol of meta-toluene diisocyanate and from 0.01 to 0.25 mol of 2 methyl, 2-4 pentanediol, said product having an amine equivalent of between 100 and 175; and from 0.4 to 25 parts by weight for each 100 parts by weight of said resin of a metallic soap powder chosen from the group consisting of Zinc stearate Strontium stearate Aluminum stearate Magnesium hydroxystearate Calcium stearate Zinc laurate Magnesium stearate Calcium oleate Barium stearate 9. A foamed cellular plastic material comprising the reaction product of an alkyd resin having a water content of from 0.1% to 3% by weight, an acid number of from 5 to 80 and wherein the hydroxyl and carboxyl groups of the alkyd resin reactants are in the ratio range of from 3(OEE-I) 1(GOOH) to 4(OH) 25(COOH) from 35 to 150 parts by weight for each 100 parts by weight of said resin of a metatoluene diisocyanate solution containing high molecular weight polyisocyanate reaction products obtained by the reaction of materials consisting of one mol of meta-toluene diisocyanate and approximately 0.01 to approximately 0.25 mol of a compound having two functional groups each of which contains a hydrogen atom that reacts with meta-toluene diisocyanate by addition polymerization, the diisocyanate polyisocyanate solution having an amine equivalent of between 100 and 175, from 0.21 to 16.5 parts by weight to each 100 parts by weight of said alkyd resin of a metal leaiing powder chosen from the group consisting of Aluminum leafing powder Aluminum bronze leanng powder Gold bronze leafing powder Copper bronze leafing powder Lead leafing powder Nickel leafing powder Silver leafing powder Gold leafing-powderl :Copper le'afing powder: 1

Calcium stearate Stainless steel leafing powder I rand from 0.21 to,16. 5 ,parts by weight to each 100 parts by weight o'f said alkyd resin of a metallic soap powder'cho'sen from the group consisting of:

Zinc stearate Strontium stearate Aluminum stearate Magnesium. hydroxystearate Z1119 laurate Magnesium'stearate' Calcium oleate Barium stearate 10. A foamed cellular plastic material comprising the reaction product on an approximate weight basis of an alkyd resin having a water content of from 0.1% to 3% by weight prepared from 4 mols trimethylol propane, 2.5 mols adipic acid and 0.5 mol phthalic anhydride and having an acid number of from 5 to from 10 to 40 grams I for each 30 grams of said alkyd resin of a product obtained by the reaction of materials consisting of approximately one mol of meta-toluene diisocyanate and from approximately 0.01 to approximately 0.25 mol of a compound having two functional groups each of which contains a hydrogen atom that reacts with the meta-toluene diisocyanate by addition reaction, the diisocyanatepolyisocyanate solution having an amine equivalent of between and 175, and from 0.4 to 0.25 part by weight for each 100 parts by weight of said resin of a metallic soap powder chosen from the group consisting of Zinc stearate Strontium stearate Aluminum stearate Magnesium hydroxystearate Calcium stearate Zinc laurate Magnesium stearate Calcium oleate Barium stearate 11. A foamed cellular plastic material comprising the reaction product of an alkyd resin having a water content of from 0.1% to 3% by weight, an acid number of from 5 to 80 and wherein the hydroxyl and carboxyl groups of the alkyl resin reactants are in the ratio range of from 3(OH) 1(COOH) to 4(OH) 5(COOH). from 35 to parts by weight for each 100 parts by weight of said resin of a meta-toluene diisocyanate solution containing high molecular weight polyisocyanate reaction products obtained by the reaction of materials consisting of one mol of meta-toluene diisocyanate and approximately 0.01 to approximately 0.25 mol of a compound having two functional groups each of which contains a hydrogen atom that reacts with the meta-toluene diisocyanate by addition polymerization, and the diisocyanate-polyisocyanate solution having an amine equivalent of between 100 and 175, from 0.21 to 16.5 parts by weight to each 100 parts by weight of said alkyd resin of a metal leafing powder, from 0.21 to 16.5 parts by weight to each 100 parts by weight of said alkyd resin of a metallic soap powder chosen from the group consisting of Zinc stearate Strontium stearate Aluminum stearate Magnesium hydroxystearate Calcium stearate Zinc laurate Magnesium stearate Calcium oleate Barium stearate and from 3.33 to 66.6 parts by weight of an unsaturated alkyl ester of aryl phosphonic acids of the general formula AIPO(OCH2CR (ll-1R where Ar represents a radical selected from the group consisting of aryl and alkaryl hydrocarbon 24 radicals and where R and R represents radicals r 1 UNITED. STATES PATENTS selected from the group consisting of'H and: alkyl Number Nam- V Date i' P 7 2,443,566 .'LOV e18. I1 d' June 15, 1948 1 Eu I 5 2,461,761 1 vNyef Feb. 15, 1949 v; FRANKW.THOMAS.

OTH R REFERENCES I De Bell-e1; a1.: German Plastics Practice, N ES T D pages 300,- 301-; 310th 31s and 46a to 485. Pub- The following-references are of record in the 10 lished by De Bell and Richardson, Sprin file of this patent? Mass., 1946. 

9. A FOAMED CELLULAR PLASTIC MATERIAL COMPRISING THE REACTION PRODUCT OF AN ALKYD RESIN HAVING A WATER CONTENT OF FROM 0.1% TO 3% BY WEIGHT, AN ACID NUMBER OF FROM 5 TO 80 AND WHEREIN THE HYDROXYL AND CARBOXYL GROUPS OF THE ALKYD RESIN REACTANTS ARE IN THE RATIO RANGE OF FROM 